Different techniques have been used to reduce the weight of a vehicle while still maintaining its structural integrity. For example, tailor welded blanks and other components are sometimes used in vehicle doors, hoods, decklids, and other bolt-on assemblies.
In the case of a tailor welded blank for a vehicle inner door panel, a piece of thin gauge metal can be used for the majority of the door panel and a stronger piece of thick gauge metal can be attached to where the door panel carries the door hinges. This way, the door panel has the requisite strength in the critical areas (i.e., where the door hinges carry the weight of the door) but is lighter in the other areas where the structural demands are not as high. However, using tailor welded blanks for non-bolt-on or weld-on assemblies, like a vehicle roof panel, can present a number of different challenges.